Gate valve



J. c. HoBBs 2,520,364

GATE VALVE 3 Sheets-Sheet l.

Aug. 29, 195o Filed Feb. 15, 1945 Aug 29, 195o J. c. HQBBS 2,520,364

GATE VALVE Filed Feb. l5, 1945 5 Sheets-Sheet 2 M fig-4 INVENTOR. 7A M55 c. ,f7/035s TTC/PNEYS Aug. 29, 1950 J. c. HoBBs 2,520,364

GATE VALVE Filed Feb. 1 5, 1945 5 Sheets-Sheet 3 IN1/EN 7A/VES C. ,L/O 5 WA4-mm A T/T/VEYS Patented ug. 29,

UNITED STATES PATENT OFFICE 8 Claims.

The present invention relates to the valve art, and particularly to a new gate valve.

The present invention makes it possible commercially to construct gate valves which are subn stantially prooi against leakage even when pipe line distortion takes place and which, as compared with prior conventional gate valves, are lighter in weight, smaller in size, lower in cost, greater in strength, and require the expenditure of much less force for opening and closing.

A gate valve embodying the present invention comprises a new combination of parts, certain of which Iare new per se, and has a new mode of operation and produces new and valuable results.

The present invention will be better understood by those skilled in the art from the following descripti-on of drawings which form a part of this specification and in which,

Figure l is a longitudinal, central, sectional view thru a gate valve embodying the present invention;

Figure 2 is an enlarged, fragmentary, detail view showing the valve parts of Fig. 1 in closed position;

Figure 3 is a transverse, sectional View take online 3-3 of Fig. 1;

Figure 4 is a sectional view taken on line-4 4 of Fig. 3;

Figures 5 and 6 are, respectively, a top plan and side elevational view of the wedge of Figs. 1 and 2 Figure 'l is a sectional view taken on line -l of Fig. 6;

Figures 8 and 9 are, respectively, top plan and side elevational views of one of the spreaders of Fig. 1;

Figure 10 is a sectional view taken on line ll-lt of Fig. 9;

Figure 1l is an enlarged fragmentary sectional view showing the sealing surfaces of the valve `of Fig. l when they are in engagement;

Figure l2 in an enlarged, central, sectional View of one of the disks of Fig, 1;

Figure 13 is a view similar to Fig. 11 but showing a modified form of sealing surfaces;

Figure 14 is a view similar to Figs. 11 and l2 but showing a further modiiied form of sealing surfaces; and,

Figure l5 is a view similar to Figs. 11, 13 and lll but showing a modified form of disk and sealing means and surfaces.

The gate valve embodying the present `invention and shown in Fig. l, comprises a valve body A, neck B and wedge unit C. Valve body A comprises a `tube i which is connected at its ends to pipes 2 as by weld metal 3. This tube I has a transverse opening li lwhich is a little more than in circumferential length and a little wider, as measured axially of tube l, than the over-all width of wedge unit 3. This opening is defined by longitudinal surfaces fia and transverse sur faces 4b. Tubular seat bodies 5 are positioned 'within tube l with their remote ends joined to tube l, as by weld metal 6, and with their adjacent ends preferably projecting slightly into opening 4 and provided with rounded seat surfaces l. It will be noted that seat bodies 5 are slightly conical with their smaller ends opposed to each other and spaced radially from the surrounding portions of Valve body l. Thus the bodies 5 are out of contact with valve body l for most of their lengths and relative movement of the valve body and the seat bodies may take place without engagement with each other particularly at the region of the free ends of the seat bodies.

Valve body l may be made from steel tubing or from a flat steel plate by bending it into tubular form and then welding it. `Such a valve body is inexpensive to make, is lighter in weight and stronger than a casting, and whatever machining is required is small in amount and may be carried out Vwith ordinary machining tools and equipment. The seat bodies 5 may be similarly constructed and possess similar characteristics. The seat bodies 5 may be provided with seating surfaces l' by simple machining operations and these surfaces may be hardened if desired prior to assembly of the seat bodies with valve body l. The seat bodies may be accurately positioned within the valve body and welded in predeterined position, thereby insuring accurate location of the seating surface 'l relative to the body l and other parts `of the valve.

Neck unit B comprises a tube lll, an end cover Il, a bonnet l2, and wedge actuating stem ll. The tube Ill is disposed with its axis at substantially right angles to valve body i and is positioned to enclose opening fl. Tube lil is cut away at one end to form tapered projections 13 which extend around body l to beyond the ends of opening ll, and the edges of projections it and the intervening end surfaces of tube l@ are connested to body l, as by weld metal le. Thus body l `and tube I9 deling chambers communicating thru opening 4.

At its outer end tube I!! is connected to cover Il, as by weld metal i5. Cover il carries a bonnet l2 which includes a hand wheel E6 equipped ywith threads to engage threads on stem ll and to move the latter endwise. Cover ll also carries tube i8 which surrounds stem I'I and acts as a stuffing box. A plurality of resilient rings I3 encircle stem I'I in tube ES and a plurality of solid, elastic, oversize rings 2@ surround stem i1 in tube I8 between rings I9. A plurality of posts 2! attached to cover I! carry a pressure plate 22 by which pressure may be exerted on sleeve 23 against the adjacent end of the packing in tube i8, the opposite end of the packing being sup- Ported against eiidWS pressure by "engagement with cove'r'll around stem il.

Tube IB may be made of steel tubing or from a bent and welded steel plate, as desired and as described above with respect to body I, and pos; sesses the desirable features of lightness, strength and low cost which are possessed by'body I. "The packing in tube Ill, composed as it is of elastic springs and elastic rings is'particularly*effectiye in preventing leakage of fluid under" pressure along stem Il and affords little frictional resistarleete eridwise movement.. of. Stem il partielllarly when supplied with lubricant as may be done. thru nipple 24- The Wedge, unit CJ as.. illustrated lil thev drew.-

ings, comprises a wedge 3d, spreaders 3l, closures or disks 3 2, and guides 33.

The. wedge @il is better Sherri irl, Fiss.- 5. 6 and l.. It; comprises a ,Slee-Shared bedr which has anv internally threa ed boss 3.2il at they `wide end for. threaded engagellentA 4vllitlfl thefelld, ef Stem I 'l w i,tr rin` body neck B, grooves 3,7, in its edges Slilliislr te. engage tlie Central ribs. an, guides 33.., and. Side. grOvOYCS. 3:3. Wbfl CQDVeTg, toward the free end thereof and are defined byv` flangesl 3 9'. 'lfhese grooves 3 8, slidably receive corresponding flanges on spreaders 3 I.

Spreaders 3j are better shown in Figs. 8 to i0. Each spreader consists of a central portion 6,5 and wirissfi. The` Centra-l portion l5 has eilt.- wardlrrreieetlris and inclined anses 4l te Sllele inl grooves,v 36 of. wedge 3i!Y and,` a central opening t0.. reeeive. stud 5.5 rreieetlns; from 'theV rear Side ofdislf; 372 Theend, of this opening, opposed to disse?. is deiiiierlby a Surface it which. Pref.- erblr. a. sesrrlefrit, of a spherical Surfaee delire@ abort. a Center. leegte@ Orl the. eelter llrie.. ef, Said @perline7 The other end et.A the, @peninshes, e Genital, Seriate. 49. to. engage. the. eenleel. Surface a., Yll.; 5,3.;hl'eQ-@- on@ th?. Stud 55.. Q; d sli 3.2,- nes it liaveileriset il. which. ereerisaserable with'the outer ribs` of guides 33, The lower @11915 0f lllges. 5.a, engage. SufaS lq-0f the Valli@ bedr? neer. erleerld ef the Strelte Qftlre wesleeend slideon those surfaces whenY the disks areVV being seat don thefseat bodies. Whenthelower ends of., y, iges 5I are in engagement with surfaces 4.a the. llrfer erde' lust Clear' the. lower. ends ef the outermribs of Yguides 33. Thev outer surface of eaohspreader 3| has a circularprojecting rib 52 to engage with the opposed rear surface of disks 32 and` limit the 'rrlo'venient of the disks relative tothespreaders.

Disks 32 have, as aforesaid, threaded studs 55 projecting fromI their' rear or outer surface, and eachhas a spherical surface naround itsstud 55 This surface is described from 'a' point on the center line of stud' byy a radius whichy is substantially tl'iesameasV4 that of spherical'su'r# face ofthe cooperating spreader @Il 'On its front face each disk Y32 Vis providedvwith a sealing surface 51 which is a segment, of afspher'e de'- scribed aboutfa point on thecenter,linefoffstud 55. The seating surface rlfmayfbe Aformedon the'v disk itself andrnay b e/hardenedif desired but, preferably, itv isfrrried bya weld, deposit composed of suitable material, such as alumi num bronze. In many instances, where conditions permit, it is desirable to provide the disks with deformable packing material such as natural or synthetic rubber as an addition to the seating surface 5l.

The guides 33 are substantially parallel plates d@ having central ribs di and side ribs 42. These guides extend from surfaces la of opening :l in valvebody, I, Where they are connected to the valve body, as by weld metal d3, nearly to cover Ivi of tube it. At their side edges they bear against and are supported by tube I9, as is better shown in Fig. 4. The middle ribs 4I engage in from the vend of the guides adjacent to closure II to points approximately in line with the adj'acentwinn'er surface of valve body I. The end anges 5I on spreaders 3! slidingly engage the inner surfaces of these 'ribs i2 during part of the mOi/.ement of the wedge. and are. out. oi enga-sement with those, ribswhen they arel in engage.- ment with surfaces lla, there being a small clearance between those flanges and ribs to permit the spreaders toslide on surfaces 4a and, bring flanges 5I underneath ribs L32.

The` guides 3,3 may be fabricated, accurately machined and hardened, if desired, as. separate pieces and then held in proper assembled. posi.- tion with respect to the valve body i while being permanently secured in place by weld metal 43. This welding operation` may be carried out readfi1y and4 easily due te the feet that it ls performed on the outside of body I.

At will, be noted from the foregoing description that the wedge unit C may` bereadily, accurately, and inexpensively made and. assembled. The guides 33 may be mil-led out of metal bars. and assembled in predetermined, position with body I and attached thereto as by welding. The wedge 3 may be machined with conventional equipment, asis also true or" the spreaders 3l, disks, 32 and nuts 5 Qf These several'partis` may be, assembled and the assembly attached to stem I7, after which ,-3 cover I may be fitted to sternV i'I and connected to tube I 0.

In Fiss. 1, 2,Y arid-f., 1- 1- the. digli 32e Carries@ ring 59 in groove (i9 just outside of weld deposit insert .Say/nich has seating surface 5l, ringA may toerist or @armatura or synthetic rubber or' rub.- ber-like material which will deform somewhat lllllerpressllre and withstand. the temperatures to which it will be subjected in use. ArsJ isfbety ter shown in Figs. 2 and. il, the ringl Egli engages 'the endof seatbody E beforefsurface'l. of the stantially the saine weld deposit- 5S with a seat,-

,ing surface 5l thereon, and the seat body has a sealing surface Y 'l-tliejreori.l The packing ring 6.0, corresponding to ringA ilofFig, il is ofless axial length than ring Eiland thedfaceof` disk 32 has been cut away near its periphery to permit the. prtlellallfylng insert. t8.. te profeet into theend of seat'body 5.. Ifand-whenring Iig- Wears away .0r-1S deferred.; Strliielentlr te' permit; Stir.'-

faces 51 and 'I will come into fluid sealing contact deposit 59a having a spherical seating surface 57a thereon and lip 6l, and may engage against ring 60ct which is of less axial length than this groove. If the ring 60a wears away or is suniciently compressed, two seals may exist. If ring 68a is omitted, surfaces 51a and 'la may come into uid sealing contact with each other.

It will be understood that the rings 59 and 60 of Figs. 2, 11 and 13 and 60a of Fig. 14 may be omitted altogether if desirable, particularly where operating conditions, such as temperature, the nature of the iiuid being handled and the like, would be detrimental to the material constituting these rings, and fluid sealing contact may be made between the cooperating spherical surfaces of the seat bodies and the disks.

Fig. 15 shows a further modification of the seat body and closure structure. The seat body 5 has a conical surface lb. The closure disk 32 has an annular inclined recess 62 in which is disposed a packing ring 53 tc engage surface lb. A. loose base `plate E4 is carried by screws 55 extending thru the disk, the periphery of plate tft having a spherical surface 66 to engage the conical surface lb of the seat body. When the disk is moved axially toward the seat body, ring 62 f engages surface 'lb and further movement brings surface 6B of plate 64 into Contact with surface '5b and exerts pressure on ring S2. Thus fluid sealing engagement by plate 64 and ring 63 with seat body 5 is accomplished.

It will be clear from an examination of Figs. 1, 1l, 13, 14 and 15 that since the surfaces 5l, 51a and 65 are spherical and make contact on the curved inner surfaces l, la and lb, the plane of contact of these surfaces is at an angle to a line perpendicular to the actual seating surfaces of the seat bodies. In other words, a seat body and its closure or disk have a common axis and that axis is not parallel to a line perpendicular to the sealing surfaces at their point of engagement. One result of this arrangement is that pressure exerted on the disk parallel to its axis is resolved into pressures exerted at an angle thereto against the seat bodies and, as a result, the latter are deflected until a continuous line contact is established and this contact may be broadened under application of greater pressure. A perfect seal is thus formed.

The mode of operation of the apparatus de scribed hereinabove and illustrated in the accompanying drawings is substantially as follows, starting at the position shown in Fig. 1: Rotation of hand wheel I 6 moves stem il' endwise toward valve body I and carries wedge unit C with it. Rotation of that unit and stem Il is prevented by engagement of the wedge 36 and spreaders Si with the ribs 6i and 42 of guides 33. Forward movement of the wedge unit C is guided by guides 33 and results in movement of the unit thru opening 4 into body l until the axes of disk studs 55 substantially coincide with the axis of body I and body seats 5. At that point spreader flanges 5| come into contact with surfaces lia of the valve body and clear the ends of ribs 42, whereupon forward movement of the spreaders and the disksis arrested. Continued movement of wedge 30 moves the spreaders apart along surfaces a until the seating surfaces of the disks engage the opposed sealing surfaces of the seat bodies 5. In other words, the wedge advances the disks toward the seat bodies. The cooperating sealing surfaces on seat bodies 5 and disks 32 and the cooperating spherical surfaces 48 of the spreaders and 5S of the disks permits shifting of the disks to positions against the bodies. This shifting may consist of slight pivoting of the disks on the spreaders. A seal is first made between each body 5 and the elastic rings, if the latter are present. Further movement makes a complete circumferential line sealing contact between the spherical surfaces of disks and the surfaces I of the seat bodies. Further movement of stem il increases the pressure of the valve disks against seat bodies 5 and increases the line contact to an area of contact due to the deformation of the engaging metal surfaces. The upper ends of spreader flanges 5i never pass entirely beyond the ends of ribs 2.

In opening the valve the initial axial movement of stem i7 moves wedge 3d relative to spreaders tracted along the axis of the seat bodies.

ing movement of stern Il moves the disks and spreaders together with the wedge 3i! out of body I thru opening 4.

It will be understood from the foregoing de-I scription that the disks are moved along a righty angle path when the valve is being opened or closed, that is, along the axis of valve body l' and also at right angles to that axis. In this manner the disks are never slid across the faces of the seat bodies but are advanced and retracted along the axes of those bodies, and when clear of those faces are moved at an angle to those axes. Thus, scratching of the sealing surfaces of the seat bodies and resultant leakage and premature poor sealing which is characteristic of prior conventional gate valves is avoided.

Valves embodying the present invention are easy to open and close and are not disorted by opening and closing movements; they are ex ceptionally free from distortion due to forces transmitted thereto by attached piping; and they are flexible in the sense that distortion of the piping and Valve body have little or no effect on the making and maintaining of a substantially fluid-tight seal. Forces which are transmitted to the valve body l by piping attached thereto and which may distort or tend to distort the valve body are sub stantially without effect on the seat bodies 5 due to the fact that each seat body is attached at one end to the valve body, is out of contact thruout substantially its full length with the valve body, and the valve body and seat bodies can move relatively toward and away from each other for substantially the full length of the seat bodies and particularly in the region of the seating` surface ends of the seat bodies. Any forces from the piping which are sufficient to distort or deflect the valve body will have substantially no effect on theseating surfaces of the seat bodies, either as regards deformation of those surfaces or displacementofthem relative to the longitudinal center` lines of theseat bodies. Furthermore,

any weakening effect of the opening 4 on valve body l is more than offset by the strengthening effect of neck B.

The opening and closing of the valve is easily accomplished because frictional forces are main tained at a minimum value. Since the valve disks are moved along substantially angular paths into and out of valve opening and closing positions, the major amount of friction to be overcome is between the wedge and spreaders and between the spreaders and surfaces lia of the valve body and end surfaces of ribs 4t2, and the pressure exerted on the cooperating surfaces of these parts is at all times quite low as compared with that present in prior wedge-type valves. Since this friction is small in amount and the valve disks are moved axially of the seat bodies when sealing contact is being made or broken, the forces required to seat the disks are low and thus actuation of the operating mechanism is comparatively easy and the actuating mechanism has little or no tendency to distort the valve body. The rounded or conical seating surfaces on the seat bodies and the spherical cooperating surfaces on the closures or disks, together with the limited freedom of movement of the valve disks relative to the spreaders, results in the disks adjusting themselves to the seat bodies and making a fluidtight contact without any scraping movement of the disks under pressure on the seating surfaces of the seat bodies. Thus, scratching of the sealing surfaces is avoi-ded over long periods of use with resultant avoidance of leakage. The fact that the seat bodies are elongated tubes and have thin walls permits the seating surface ends oi' those bodies to distort or deflect slightly to accommodate themselves to the sealing surfaces of the disks and to maintain sealing contact with the disks even in case the seat bodies are de# rlected by forces transmitted thereto thru the valve body from the piping.

Having thus described my invention so thatv others skilled in the art may be able to understand and practice the same, I state that what I desire to secure by Letters'Patent is'dened in what is claimed.

What is claimed is:

1. AY gate valve comprising a valvebo'dyhavin'g opposedr seating surfaces, discs maintained out of. contact with said body and having surfaces to engage said seating surfaces and close the valve, spreaders carrying said discs and having spherical surface engagement with central'parts thereof having opposite end surfaces, a wedge slidably engaging and carrying said spreaders, means in the body engaging and guiding said wedge and spreaders during their movement transversely of saidbody, pairs of guidesl in the body, each pair engaging the end surfaces of said spreaders when the discs are in approximate alignment with said seating surfaces for guiding said spreaders during their movement longitudinally of the body Yas the discs are moved into and out of engagement with' said seating surfaces, and means for moving the wedge-spreader-disc assembly to open or close the valve.

2. Agate valve'comprising a cylindrical memher enclosing sea-t tubes, seating surfaces on opposedfends of said tubes, and a gate-assemblyenclosing tube extend-ing transversely from said member, d-iscs maintained out of contact-with said member and'having surfaces to engage said seating surfaces and closethe valve, spreaders carrying said discs and having surface engagen ment with central parts thereof and havingopposite end surfaces, a wedge slidably engaging and carrying said spreaders, means in the cylindrical member engaging and guiding said wedge and spreaders during their movement transversely of said cylindrical member, said means including a pair of machined guides on opposite edges of said wedge and spreaders within said transverse tube and connected to said cylindrical member, pairs of guides in the member, each pair engaging opposite end surfaces of said spreaders when the discs are in approximate alignment with said seating surfaces for guiding said spreaders during their movement longitudinally of the member as the discs are moved into and out of engagement with said seating surfaces, and means for moving the wedge-spreader-disc assembly to open or close the valve.

3. A gate valve comprising a cylindrical member including opposed. seating surfaces, discs maintained out of contact with said member and having surfaces to engage said seating surfaces and close the valve, spreaders carrying said discs and having surface engagement with central parts thereof and having opposite end surfaces, a wedge siidably engaging and carrying said spreaders, means in said member engaging and guiding said wedge and spreaders during their movement transversely of said member, said means comprising a pair of machined transverse guides engaging the edges of said wedge and spreader-s and secured at their inner ends to the cylindrical member near the intersection there with of a longitudinal plane through the center of the member, a tube positioned at right angles to said member outside of said guides and se cured to the outer surfaces of said guides adjacent to their attachments to said member, pairs of longitudinal guides in the member, each pair engaging opposite end surfaces of said spreaders when the discs are in approximate alignment with said seating surfaces for guiding said spreaders during their movement longitudinally of the body as the discs are moved into and out of engagement with said seating surfaces, and means for moving the wedge-spreaden-disc asn sembly to open or close the valve.

4. A gate valve comprising a valve body having opposed seating surfaces, discs maintained out of .contact with said body, having surfaces to engage said seatingV surfaces and close the valve, and having projecting central portions, spreaders attached to said central portions for limited relative movement of the spreaders and discs and having opposite end surfaces, a wedge slidably engaging and interlocking with said spreaders for relative movement in only one plane, means in the body engaging and guiding said wedge and spreaders during their movement transversely of said body, pairs of guides in the body, each pair engaging opposite end surfaces of said spreaders for guiding said spreaders when the discs are in approximate alignment with said seating surfaces during their movement longitudinally of the body as the discs are moved into and out of engagement with said seating surfaces, and means for moving the wedge-spreaderdisc assembly to open or close the valve.

5. A gate valve comprising a valve body having opposed seating surfaces, discs maintained out of contact with said body, having surfaces to engage said seating surfaces and' close the valve, and having central projecting portions, spreaders carrying saiddiscs and having surface engagen ment with said central portions and having' opposite end surfaces, said spreaders having opposite side transverse flanges and parallel longitudinal end surfaces, a wedge carrying said spreaders and having flanges at its opposite edges, opposed guides having ribs engaging the flanges of said spreaders and Wedge for guiding the spreaders and Wedge during their movement transversely of the body, pairs of guides in the body engaging the end surfaces of said spreaders when the discs are in approximate alignment with said seating surfaces for guiding said spreaders during their movement longitudinally of the body as the discs are moved into and out of engagement with said seating surfaces, and means for moving the wedge-spreader-disc assembly to open or close the valve.

6. A gate valve comprising a valve body having opposed seating surfaces, discs having axial portions and having annular surfaces to engage said seating surfaces and close the valve, spreaders attached to said axial portions and maintaining said discs out of contact with body while permitting limited movement about the axes of said portions and having opposite end surfaces, a Wedge slidably engaging and carrying said spreaders, means in the body for guiding said Wedge and spreaders during their movement transversely of said body, and pairs of guides in the body and each pair engaging the end surfaces of said spreaders lwhen the discs are in approximate alignment With said seating surfaces for guiding said spreaders during their movement longitudinally of the body as the discs are moved into and out of engagement with said seating surfaces, and means for moving the Wedgespreader-disc assembly to open or close the valve.

7. A gate valve comprising a body having opposed seating surfaces therein, discs maintained out of contact with said body, spreaders having opposite ends, carrying said dises and having connection with -central portions thereof, a Wedge slidably connected to said spreaders, guides extending transversely of said body and'engaging opposite ends of said spreaders and Wedge for directing the travel of said spreaders and wedge transversely of said body, and guides in the body and engaging the opposite ends of the spreaders when the dises carried thereby are in substantial alignment vvith said surfaces for directing travel of said spreaders longitudinally of the body to move the discs into and out of engagement with said seating surfaces, and means for moving the spreaders along said transverse and longitudinal guides,

8. A gate valve comprising a fabricated tube body having a transverse, valve receiving opening extending throughout substantially 180 thereof, two fabricated tubes disposed Within said body, Welded thereto at their remote ends and having their adjacent ends formed with valve seating surfaces disposed in approximate transverse alignment with the sides of said opening, said tubes being out of contact with said body for the major part of their lengths from their seating surface ends toward their Welded ends, premachined guides seated at their inner ends on the opposite ends of said opening and attached by Weld metal to the adjacent outer surface of said body, a fabricated tubular neck disposed at substantially right angles to said body, having an annular end surface seating thruout substantially its full length on the outer surface of said body and enclosing said guides and opening, and Weld metal connecting said end surface thruout its entire circumferential length to the outer surfaces of said guides and body.

JAMES C. HOBBS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 270,009 Burns Jan. 2, 1883 680,714 Jefferson Aug. 20, 1901 712,682 Jefferson Nov. 4, 1902 791,173 Anglim May 30, 1905 904,056 Farrell Nov. 17, 1908 2,034,418 Plant Mar. 17, 1936 2,100,996 Moore Nov. 80, 1937 2,114,789 Urquhart Apr. 19, 1938 2,401,377 Smith June 4, 1946 FOREIGN PATENTS Number Country Date 678 Great Britain Feb. 24, 1875 10,188 Great Britain May 23, 1895 82,802 Sweden Mar. 5, 1935 529,169 Germany July 1, 1931 735,816 France Sept. 6, 1932 770,610 France July 2, 1934 

